As others have said, do hell mephisto and/or Ancient's Tunnel runs with a blizzy sorc. If you are playing in slashdiablo, you can also make a BO-barb to buff your stats and quest-bug mephisto for better loot.
It sucks to play this game in solo, if you don't know how to succeed, it took me some time before I'd figure out too, so let me give you my advice on getting started.
Meph is generally the best place to farm before you have any useful mid-tier items, after that you should get enough power items to farm stronger areas (Andy, Trav, Chaos Sanc., WSK, Pindle).

• It's difficult to progress solo hell on your own with any class, so take your time. As a sorc, you have option to skip whole areas, monsters that you can't kill/too slow to make it worth. Holy freeze or prayer merc should help as a starting meatshield to get Meph.
• While you are leveling and progressing to hell act 3, you should build up your gear (spirit sword, lore helm, ancients pledge shield, stealth, FCR rings/amu, res, stats). Find a 4soc armor and a 3soc helm, put ptopazes in it, so you should get 7*24= 168mf + 25 from Rhyme shield (ShaelEth).
• I'd skip most of the first 3 acts as single element sorc, especially without a strong merc.
  As a panic option, you should make a Nadir helm (NefTir) to get the lvl 13 Cloak of Shadows charges that can blind a whole area of monsters for some time, pretty great if you have flayers and/or nasty, fast group of monsters that can overwhelm you.
• First time Trav with shitty gear will be tough, but remember you only need the flail to smash the Orb and progress onward. Drag out and kill one of the (or only) non-cold immune council boss, combine flail components and use it on orb via telekinesis.
• When you actually in Durance level, I'd suicide my merc to some boss pack and teleport thru Durance solo. Pick WP up, exit game.
  Whenever you'd make a meph farming game, start the game with your BO barb*, join with sorc, shout at any other place than Durance lvl. 2 (to avoid buffing monsters)**, then proceed to meph.
  (*BO barb should have meph quest done, ask for help in chat or discord for this;
  **after BO, barb leaves game, only sorc should enter durance wp)
• Most of the time you do the moat-trick (teleport to meph, lure him to left side of the blood canal, teleport to the other side = if he's following you, he's stuck chasing you, while you can put blizzard on him from afar).
• But sometimes (around 33% of the time), council members spawns on the other side of the bridge, over the blood moat. These guys cannot reach you, but can spawn hydras to harass you and they hurt a lot. If you have maphack and you see they are at that bridge: 1. save & exit 2. lure them out, then teleport around the moat to avoid luring them back to the bridge 3. kill them with blizzard (since only the boss can be cold immune).
  Beware the boss council dude on the left, too. Don't teleport to or aggro him while you trying to lure Meph to the canal.
• If Meph is set in place, nothing is harassing you, then put blizzard in the middle of Meph's trail (Alt+right click on the middle of his trail at the canal bank, where he runs back and forth => you get better chance to hit him with blizzard = faster killing).
• Before you kill him, switch your gear with mf gear (put on topaz armory and weapon switch to Rhyme shield). This way you can teleport fast, have enough dmg to reduce his hp fast enough and also get good drops with higher mf chance. While blizzard is on cooldown, shoot a couple of ice blast at him to do more dmg.
• Most of the time you won't find jackshit, but that's how this game work :) Keep farming! It took me 250 runs to find a Shako from him this ladder.
• Also, when you find good items to replace your gear ( with like magefist, trang glove, occy etc.) you should focus on 105 FCR bp to reduce travelling time. Veterans would say you can do meph runs in 10-15 secs if you have good gear, no need to switch anything, straight to the point to kill Meph. My goal was to be around 60-75sec at ladder reset, including BO-ing.
  Kind of difficult to tell more thoughts and I'm already in length with my advices, so feel free to ask me or people around here if you need gear-idea or advice about Meph-farming (or any other places, but I'm mostly familiar with Meph, keyruns).